here i was more thinking KV series of tanks, which russia produced more than 5000 off.
the cold war relatively quickly saw a push away from heavy and medium tanks towards the Main Battle Tank concept, which is what most tanks today are with only the odd light tank standing out.
yes but they are unreliable and often quiet suicidal to perform. now to be fair the vision of tanks wasn’t always the greatest but almost all of those weapons weren’t effective at more than a 100 meters, a fair few require being within meters like the molotov, stick grenades or magnetic mines, which ideally a tank would be protected against by infantry.
anti tank rifles existed, in fact they still sort of exist today, though usually we call them “anti material rifles” today due to the fact they are really more useful vs things like mines and lightly armoured, or no armour, vehicles. but while they in WW1 could kill the crew of a tank by WW2, esp towards the mid and late period, they became less and less effective at that, instead at best being able to take out tracks etc.
as for the molotov cocktail its name comes from the Finnish war, as a joke against the soviet foreign minister.
most of the worlds armies have some form of conscription system meant to supplement the army in case of a need for national defence, which allows the armies to expand quiet rapidly when needed.
my country (Denmark) has an on paper strength of about 20k+another 12k in the ready reserve and 100s of thousands in the secondary reserves, the 20k are really more the professional soldiers & sailors and specialist like officers, pilots etc. while the plan always is to be able to expand rapidly if need be.
and that is how it is for a lot of countries.